But users most frequently stayed in Iowa's largest metro area last year.

With 25,000 guest arrivals, Polk County was the state's most popular destination. Bookings in the county brought in $2.4 million.

Johnson County, home to the University of Iowa, brought in the second-largest count with 9,500 arrivals and $970,000 in revenue.

Still, Airbnb is a popular booking tool in smaller, more rural areas. The San Francisco-based company reported 3.3 million guest arrivals at rural U.S. listings in June 2017 – a year-over-year increase of 138 percent.

Last year, Winneshiek County, population 21,000, was Iowa's third most popular destination with 6,400 bookings and $551,000 in revenues.

That county, home to Decorah, beat out Linn, Scott and Story counties – all home to larger metropolitan areas.

In its news release, Airbnb said its growth here has not come at the expense of the hotel and motel industry. Officials pointed to data from Smith Travel Research that show steady hotel occupancy rates in Iowa through November 2018.

"Statewide data indicates that Airbnb and its host community appear to be complementing – rather than competing with – the Iowa hotel industry," the news release said.

Airbnb said its service "is opening up the state to a new slice of prospective tourists" by catering to those who want to stay in neighborhoods, save money or stay at destinations not served by hotels.

But Craig Walter, executive vice president of the Iowa Lodging Association, said hotels and Airbnbs draw from the same pool of customers.

"So if you bring on a 100-unit hotel or you bring on 10 or 15 Airbnbs, they’re all taking from the market," he said.

Walter said most hotel operators haven't seen a huge impact from Airbnb's growth in Iowa.

He said the service is welcome competition, so long as all Airbnb hosts pay the same taxes as hoteliers (Airbnb noted it paid $900,000 in Iowa state, city and county taxes in the first year of its tax agreement with the Iowa Department of Revenue).

"Competition is welcome as long as we all play by the same rules," he said. "It's not a problem."

Walter said the hotel business remains strong in Iowa, particularly in its biggest cities. It's bed-and-breakfast operators who are most likely to suffer from the growth of Airbnb and other similar services.

Iowa was once home to 200 to 300 bed-and-breakfast operations, Walter said. But their ranks have halved in recent years.

Whether they're staying at a hotel or a funky Airbnb, Walter said lodging is not driving travelers' decisions to visit Iowa.

"People don't come to a community to stay at a particular hotel or Airbnb," he said. "There has to be a reason. Most is business driven."